Daptomycin, part of a new class of antibiotics currently approved only for use in adults, is effective and well-tolerated in children with Methicillin-resistant Staphylococcus aureus (MRSA), according to a study published in the March 2017 issue of the journal Pediatrics.

"The safety and efficacy of intravenous daptomycin was comparable to standard-of-care IV antibiotics used for hospitalised children, usually vancomycin or clindamycin for MRSA and cefazolin for methicillin-susceptible strains of S aureus," said John Bradley, MD, University of California at San Diego School of Medicine, San Diego, California.

"Daptomycin should provide a safe and effective alternative to vancomycin, clindamycin or linezolid for IV treatment of invasive MRSA skin infections," he said. "Concerns for vancomycin renal toxicity and clindamycin antibiotic resistance were not present. There was no evidence of daptomycin toxicity in the trial."

The US Food and Drug Administration (FDA) is currently reviewing whether to approve daptomycin use in children.

Community-associated MRSA (CA-MRSA) usually causes skin infections but can lead to more serious consequences, such as pneumonia and infections of bones and joints. Daptomycin is active against MRSA and was approved for use in adults in 2003 for treatment of skin and skin structure infections, and for bloodstream infections 3 years later.

The current prospective, randomised, investigator-blinded study included more than 250 daptomycin-exposed children aged 1 to 17 years to document safety and efficacy of the antibiotic in treating paediatric skin and skin structure infections.

Dosing was based on adult experience, but researchers found that the younger the child, the more quickly their bodies eliminated daptomycin. Thus paediatric doses increased as the age of the research participants decreased.

"Most news these days is about the declining utility of antibiotics as microbial resistance becomes more widespread and intractable," said Dr. Bradley. "These findings are encouraging. Daptomycin appears to be a suitable, once-a-day alternative to existing antibiotics with harsher side effects."